Machines for packing food products, for example packaging containers with liquid foods such as, for example, juice, milk, etc. or foods of a more solid nature such as, for instance, soups, vegetables etc. often have a production line with conveyors for conveying the packaging containers during different phases along the production line. These phases may consist of one or more filling steps, sealing steps or folding steps in a series of different combinations, or may comprise other functions.
In or before, for example, a folding- or sealing step, the moving packaging container and those devices which fold or seal the packaging container must be in the correct orientation in relation to one another so that the folding or sealing operation may be carried out correctly. In principle, there are two variations of orientation. Either each packaging container maintains its orientation in which event the device for folding or sealing, respectively, is oriented in relation to the moving packaging container, i.e. the device for folding or sealing adapts its orientation. Alternatively, each packaging container is rotated, i.e. oriented in the correct orientation and the device for folding or sealing is stationary. This latter alternative usually gives a higher degree of reliability in folding or sealing of packaging containers in motion. One method of realising this orientation of the packaging containers is to employ a conveyor with a rotating device which changes their orientation, i.e. rotates the containers from a first to a second orientation so that a different side of the packaging container which, for example, is at right angles to and adjacent in relation to the front side in the first orientation becomes the front side in a second orientation in the continued direction of movement on the conveyor. Naturally, both of these methods of orientation may be combined so that both the package and the folding devices carry out a part of the orientation movement.
Publication WO 0228716 describes an apparatus for turning packaging containers in a filling machine. This apparatus receives, moves, rotates and passes on moving packaging containers, from an incoming first orientation to a second orientation. The apparatus discharges the moving packaging containers in the same direction of movement in their second orientation as in their first orientation, but the packaging containers have been rotated through 90°. The rotation is put into effect by a sweeping movement, and the apparatus consists of a rotating wheel on which carrier units are rotatably secured. Each carrier unit is secured via a carrier shaft which extends axially through the rotating wheel with its axis of rotation parallel with the axis of rotation of the rotating wheel. However, it has proved that this construction suffers from a number of drawbacks which occur principally when the apparatus is run at a high speed. Problems which have occurred are, for example, that the package may be damaged when the carrier unit holds or discharges the package and that the package occasionally shows a tendency to jump out of the subsequent part of the machine in connection with discharging from the carrier unit.